
73Oxygen Production
steam is typically directly injected into a water bath
maintaining the bath temperature. Tubes are arranged
within the water bath. As the cryogen is vaporized,
the water temperature drops and steam is automati-
cally injected to maintain bath temperature. An alter-
nate type of steam vaporizer has tubes within an HP
shell containing steam. The steam is condensed and
removed in steam traps. This direct steam vaporizer
is generally lower cost but produces a variable prod-
uct outlet temperature. On loss of steam, there is also
an immediate loss of product backup. A water bath
has signicant ballast. Natural gas is used in a si ...